title: The ovary of the desert locust Schistocerca gregaria contains a glycine- and proline-rich peptide that displays sequence similarities with a new class of GPRP proteins from plants.
abstract: A novel, highly hydrophobic, glycine- and proline-rich peptide was characterized in the ovary of the desert locust, Schistocerca gregaria. The peptide was detected as one of the major peaks in a chromatographic separation of an acidic methanolic extract of 50 mature ovaries. Electrospray mass spectrometry yielded a molecular mass of 6305 Da. The partial amino acid sequence as determined by Edman degradation based automated microsequencing is as follows: Ala-Tyr-Pro-Ala-His-Gln-Gly-Tyr- Pro-Ala-His-Val-Gly-Tyr-Ala-Arg-Val-Gly-Tyr-Gly- Gly-Tyr-Pro-Ser-Tyr-Gly-Tyr-Pro-Ala. Four amino acids (Gly, Pro, Ala, and Tyr) account for more than 80% of the composition of this sequence. Gly-Tyr-Pro is the most important repetitive motif. Ala-Tyr-Pro, Gly-Tyr-Gly and Gly-Tyr-Ala occur as variations of this motif. The novel glycine- and proline-rich insect peptide displays structural characteristics similar to those of a new class of glycine- and proline-rich proteins (GPRP) that have recently been identified in Arabidopsis thaliana (thale cress) and Daucus carota (carrot). The GPRP of A. thaliana contains the same repetitive motifs (except for Ala-Tyr-Pro), the Gly-Tyr-Pro motif also being the most abundant.
authors.affiliation: Zoological Institute, Katholieke Universiteit Leuven, Belgium. liliane.schoofs@bio.kuleuven.ac.be
authors.forename: L
authors.initials: L
authors.lastname: Schoofs
authors.forename: A
authors.initials: A
authors.lastname: Hamdaoui
authors.forename: B
authors.initials: B
authors.lastname: Devreese
authors.forename: J
authors.initials: J
authors.lastname: Van Beeumen
authors.forename: A
authors.initials: A
authors.lastname: De Loof
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017360:Arabidopsis / Q000737:chemistry; D029681:Arabidopsis Proteins; D018552:Daucus carota / Q000737:chemistry; D005260:Female; D006110:Grasshoppers / Q000737:chemistry*; D008969:Molecular Sequence Data; D010053:Ovary / Q000737:chemistry; D010455:Peptides / Q000737:chemistry* / Q000302:isolation & purification; D010940:Plant Proteins / Q000737:chemistry*; D017421:Sequence Analysis; D017386:Sequence Homology, Amino Acid
chemical_list: D029681:Arabidopsis Proteins; C099006:GPRP protein, Arabidopsis; D010455:Peptides; D010940:Plant Proteins